It’s often said, very accurately, that change is the only constant in life.

In the 21st century, with change accelerating faster than ever before, managing it in the public interest has become one of the greatest challenges for government.

This is particularly important when it comes to infrastructure in our cities and regions, which must be constantly reviewed and renewed in accordance with those changing needs.

We must not only anticipate the future, we must take appropriate steps to shape it.

Australia’s population will hit 25 million today. Such strong population growth and changes in work patterns are fundamentally altering the face of Australia’s capital cities.

Cities are booming.

They are expanding outwards and upwards amid strong population growth and jobs growth in and around their central business districts.

Governments need to invest in the railways and roads required to accommodate this growth in order to alleviate traffic congestion, which undermines our quality of life.

It’s a pity that former Prime Minister Tony Abbott lacked vision when, in 2013, he cancelled all federal investment in public transport projects in our cities.

Indeed, the experts tell us that traffic congestion is costing the nation more than $16 billion a year in lost productivity, with the figure expected to hit $53 million a year by 2031 unless we take action now.

While Mr Abbott’s successor Malcolm Turnbull offers rhetorical support for public transport, he has refused to reinstate Mr Abbott’s cuts to Federal investment.

Mr Turnbull likes to take selfies on trains and trams; he just won’t invest in trains and trams.

Instead of seeing public transport as a photo opportunity, Mr Turnbull should understand it for what it is – an essential public service that will become increasingly important as our population continues to grow over coming decades.

We need to invest now. In spite of this, 85 percent of the investment the Coalition says it will make in public transport in coming years won’t appear before the next two elections.

We need to look beyond immediate politics and towards the need of a dynamic future.

Better public transport is only part of the equation when it comes to less congested, more successful cities.

A great way to ease pressure on capital cities is to promote growth and economic development of regional centres.

When it comes to Australia’s east coast, genuine decentralisation should include construction of a High Speed Rail Link between Brisbane and Melbourne via Sydney and Canberra.

High Speed Rail would revolutionise interstate travel on Australia’s eastern coast, allowing people to travel between capital cities in as little as three hours.

But it would also turbo charge the economic development of the regional cities along its route, including the Gold Coast, Casino, Grafton, Coffs Harbour, Port Macquarie, Taree, Newcastle, the Central Coast, Southern Highlands, Wagga Wagga, Albury-Wodonga and Shepparton.

High Speed Rail could make it possible for people to live in regional areas and commute to the city. Even better, it could enable companies to establish their offices and factories in regional centres, where they could take advantage of lower overheads while also knowing their capital city markets were just a short train ride away.

A feasibility study conducted by the former Labor Government found High Speed Rail was viable and would return more than $2 in economic benefit for every dollar invested.

We also appointed an expert panel which recommended the creation of a High Speed Rail Authority to commence detailed planning and begin to acquire the corridor before it was built out by urban sprawl.

But again, Tony Abbott dumped the idea. And again, Mr Turnbull, who presents himself as a rail enthusiast, has failed to put it back in place.

High Speed Rail will happen one day. The need for decentralisation makes it inevitable. Even if we don’t want to build it tomorrow, we should secure the corridor now so it can proceed in the future.

In fact, we should have started securing the corridor back in 2013.

In the same way, we should be acquiring the corridors for other rail and road projects that we know will happen in the future.

Indeed, the independent Infrastructure Australia produced a report last year calling for a formal program of corridor acquisition for future infrastructure projects.